Andi Kleen 69b4573296 Cache xattr security drop check for write v2 ... Some recent benchmarking on btrfs showed that a major scaling bottleneck on large systems on btrfs is currently the xattr lookup on every write. Why xattr lookup on every write I hear you ask? write wants to drop suid and security related xattrs that could set o capabilities for executables. To do that it currently looks up security.capability on EVERY write (even for non executables) to decide whether to drop it or not. In btrfs this causes an additional tree walk, hitting some per file system locks and quite bad scalability. In a simple read workload on a 8S system I saw over 90% CPU time in spinlocks related to that. Chris Mason tells me this is also a problem in ext4, where it hits the global mbcache lock. This patch adds a simple per inode to avoid this problem. We only do the lookup once per file and then if there is no xattr cache the decision. All xattr changes clear the flag. I also used the same flag to avoid the suid check, although that one is pretty cheap. A file system can also set this flag when it creates the inode, if it has a cheap way to do so. This is done for some common file systems in followon patches. With this patch a major part of the lock contention disappears for btrfs. Some testing on smaller systems didn't show significant performance changes, but at least it helps the larger systems and is generally more efficient. v2: Rename is_sgid. add file system helper. Cc: chris.mason@oracle.com Cc: josef@redhat.com Cc: viro@zeniv.linux.org.uk Cc: agruen@linbit.com Cc: Serge E. Hallyn <serue@us.ibm.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>		2011-05-28 12:02:09 -04:00
..
9p	9p: remove unnecessary dentry_unhash on rmdir, dir rename	2011-05-28 01:02:53 -04:00
adfs	Fix common misspellings	2011-03-31 11:26:23 -03:00
affs	affs: remove unnecessary dentry_unhash on rmdir, dir rename	2011-05-28 01:02:53 -04:00
afs	afs: remove unnecessary dentry_unhash on rmdir, dir rename	2011-05-28 01:02:53 -04:00
autofs4	vfs: push dentry_unhash on rmdir into file systems	2011-05-26 07:26:47 -04:00
befs	Fix common misspellings	2011-03-31 11:26:23 -03:00
bfs	bfs: remove unnecessary dentry_unhash on dir rename	2011-05-28 01:02:50 -04:00
btrfs	fs: pass exact type of data dirties to ->dirty_inode	2011-05-27 07:04:40 -04:00
cachefiles	Fix common misspellings	2011-03-31 11:26:23 -03:00
ceph	ceph: remove unnecessary dentry_unhash calls	2011-05-26 07:26:53 -04:00
cifs	cifs: remove unnecessary dentry_unhash on rmdir/rename_dir	2011-05-26 07:26:59 -04:00
coda	coda: remove unnecessary dentry_unhash on rmdir, dir rename	2011-05-28 01:02:53 -04:00
configfs	configfs: remove unnecessary dentry_unhash on rmdir, dir rename	2011-05-28 01:02:54 -04:00
cramfs
debugfs	debugfs: move to new strtobool	2011-05-19 16:55:28 +09:30
devpts	fs/devpts/inode.c: correctly check d_alloc_name() return code in devpts_pty_new()	2011-03-22 17:44:17 -07:00
dlm	Merge branch 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6	2011-05-26 13:19:00 -07:00
ecryptfs	ecryptfs: remove unnecessary dentry_unhash on rmdir, dir rename	2011-05-28 01:02:52 -04:00
efs	block: remove per-queue plugging	2011-03-10 08:52:07 +01:00
exofs	exofs: remove unnecessary dentry_unhash on rmdir/rename_dir	2011-05-26 07:26:57 -04:00
exportfs	vfs: Add open by file handle support	2011-03-15 02:21:44 -04:00
ext2	ext2: remove unnecessary dentry_unhash on rmdir/rename_dir	2011-05-26 07:26:56 -04:00
ext3	fs: pass exact type of data dirties to ->dirty_inode	2011-05-27 07:04:40 -04:00
ext4	fs: pass exact type of data dirties to ->dirty_inode	2011-05-27 07:04:40 -04:00
fat	fat: remove unnecessary dentry_unhash on rmdir, dir rename	2011-05-28 01:02:54 -04:00
freevxfs	treewide: fix a few typos in comments	2011-05-10 10:16:21 +02:00
fscache	fscache: remove dead code under CONFIG_WORKQUEUE_DEBUGFS	2011-05-25 08:39:44 -07:00
fuse	fuse: remove unnecessary dentry_unhash on rmdir, dir rename	2011-05-28 01:02:53 -04:00
gfs2	Merge branch 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6	2011-05-26 13:19:00 -07:00
hfs	hfs: remove unnecessary dentry_unhash on rmdir, dir rename	2011-05-28 01:02:52 -04:00
hfsplus	hfsplus: remove unnecessary dentry_unhash on rmdir, dir rename	2011-05-28 01:02:52 -04:00
hostfs	hostfs: remove unnecessary dentry_unhash on rmdir, dir rename	2011-05-28 01:02:52 -04:00
hpfs	hpfs: remove unnecessary dentry_unhash on rmdir, dir rename	2011-05-28 01:02:54 -04:00
hppfs
hugetlbfs	mm: don't access vm_flags as 'int'	2011-05-26 09:20:31 -07:00
isofs	Merge branch 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block	2011-03-24 10:16:26 -07:00
jbd	jbd: Fix comment to match the code in journal_start()	2011-05-24 00:27:53 +02:00
jbd2	Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4	2011-05-26 09:53:20 -07:00
jffs2	jffs2: remove unnecessary dentry_unhash from rmdir, dir rename	2011-05-28 01:02:50 -04:00
jfs	jfs: remove unnecessary dentry_unhash from rmdir, dir rename	2011-05-28 01:02:51 -04:00
lockd	NLM: Fix "kernel BUG at fs/lockd/host.c:417!" or ".../host.c:283!"	2011-01-25 15:24:47 -05:00
logfs	logfs: remove unnecessary dentry_unhash from rmdir, dir rename	2011-05-28 01:02:51 -04:00
minix	minix: remove unnecessary dentry_unhash on rmdir, dir rename	2011-05-28 01:02:54 -04:00
ncpfs	ncpfs: fix rename over directory with dangling references	2011-05-28 01:02:53 -04:00
nfs	nfs: remove unnecessary dentry_unhash on rmdir/rename_dir	2011-05-26 07:26:57 -04:00
nfs_common	Fix common misspellings	2011-03-31 11:26:23 -03:00
nfsd	treewide: fix a few typos in comments	2011-05-10 10:16:21 +02:00
nilfs2	nilfs2: remove unnecessary dentry_unhash from rmdir, dir rename	2011-05-28 01:02:51 -04:00
nls
notify	Merge branch 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6	2011-04-07 11:14:49 -07:00
ntfs	Fix common misspellings	2011-03-31 11:26:23 -03:00
ocfs2	Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2	2011-05-26 10:55:15 -07:00
omfs	omfs: remove unnecessary dentry_unhash on rmdir, dir rneame	2011-05-28 01:02:52 -04:00
openpromfs
partitions	fs/partitions/efi.c: corrupted GUID partition tables can cause kernel oops	2011-05-26 17:12:37 -07:00
proc	fs/proc/vmcore.c: add hook to read_from_oldmem() to check for non-ram pages	2011-05-26 17:12:37 -07:00
pstore	pstore: fix pstore filesystem mount/remount issue	2011-05-16 11:05:00 -07:00
qnx4	block: remove per-queue plugging	2011-03-10 08:52:07 +01:00
quota	vmscan: change shrinker API by passing shrink_control struct	2011-05-25 08:39:26 -07:00
ramfs	ramfs: fix memleak on no-mmu arch	2011-04-14 16:06:56 -07:00
reiserfs	reiserfs: remove unnecessary dentry_unhash from rmdir, dir rename	2011-05-28 01:02:51 -04:00
romfs
squashfs	Merge git://git.kernel.org/pub/scm/linux/kernel/git/pkl/squashfs-linus	2011-05-26 17:27:35 -07:00
sysfs	sysfs: remove "last sysfs file:" line from the oops messages	2011-05-13 16:05:51 -07:00
sysv	sysv: remove unnecessary dentry_unhash from rmdir, dir rename	2011-05-28 01:02:50 -04:00
ubifs	ubifs: remove unnecessary dentry_unhash from rmdir, dir rename	2011-05-28 01:02:51 -04:00
udf	udf: remove unnecessary dentry_unhash from rmdir, dir rename	2011-05-28 01:02:52 -04:00
ufs	ufs: remove unnecessary dentry_unhash from rmdir, dir rename	2011-05-28 01:02:51 -04:00
xfs	fs: pass exact type of data dirties to ->dirty_inode	2011-05-27 07:04:40 -04:00
aio.c	Merge branch 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block	2011-03-24 10:16:26 -07:00
anon_inodes.c	sanitize vfsmount refcounting changes	2011-01-16 13:47:07 -05:00
attr.c	Cache xattr security drop check for write v2	2011-05-28 12:02:09 -04:00
bad_inode.c
binfmt_aout.c
binfmt_elf.c	brk: COMPAT_BRK: fix detection of randomized brk	2011-04-14 16:06:55 -07:00
binfmt_elf_fdpic.c
binfmt_em86.c
binfmt_flat.c	CRED: Fix load_flat_shared_library() to initialise bprm correctly	2011-05-03 10:10:51 +10:00
binfmt_misc.c
binfmt_script.c
binfmt_som.c
bio-integrity.c	block: Require subsystems to explicitly allocate bio_set integrity mempool	2011-03-17 11:11:05 +01:00
bio.c	vfs: Improve the bio_add_page() and bio_add_pc_page() descriptions	2011-05-27 09:43:00 -04:00
block_dev.c	block: move bd_set_size() above rescan_partitions() in __blkdev_get()	2011-05-23 08:50:48 -07:00
buffer.c	fs: block_page_mkwrite should wait for writeback to finish	2011-05-28 01:03:21 -04:00
char_dev.c
compat.c	exec: unify do_execve/compat_do_execve code	2011-04-09 15:53:56 +02:00
compat_binfmt_elf.c
compat_ioctl.c
dcache.c	vmscan: change shrinker API by passing shrink_control struct	2011-05-25 08:39:26 -07:00
dcookies.c
direct-io.c	Merge branch 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block	2011-03-24 10:16:26 -07:00
drop_caches.c	vmscan: change shrinker API by passing shrink_control struct	2011-05-25 08:39:26 -07:00
eventfd.c	Docbook: add fs/eventfd.c and fix typos in it	2011-02-21 15:07:04 -08:00
eventpoll.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
exec.c	coredump: add support for exe_file in core name	2011-05-26 17:12:36 -07:00
fcntl.c	userns: rename is_owner_or_cap to inode_owner_or_capable	2011-03-23 19:47:13 -07:00
fhandle.c	fs/fhandle.c: add <linux/personality.h> for ia64	2011-04-14 16:06:56 -07:00
fifo.c	Filesystem: fifo: Fixed coding style issue.	2011-03-21 00:16:09 -04:00
file.c	vfs: avoid large kmalloc()s for the fdtable	2011-04-28 11:28:20 -07:00
file_table.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2011-03-16 13:26:17 -07:00
filesystems.c	fs: synchronize_rcu when unregister_filesystem success not failure	2011-04-17 10:42:01 -07:00
fs-writeback.c	fs: pass exact type of data dirties to ->dirty_inode	2011-05-27 07:04:40 -04:00
fs_struct.c	sanitize vfsmount refcounting changes	2011-01-16 13:47:07 -05:00
generic_acl.c	userns: rename is_owner_or_cap to inode_owner_or_capable	2011-03-23 19:47:13 -07:00
inode.c	fs: cosmetic inode.c cleanups	2011-05-27 09:43:00 -04:00
internal.h	fs: move i_wb_list out from under inode_lock	2011-03-24 21:17:51 -04:00
ioctl.c	vfs: cleanup do_vfs_ioctl()	2011-03-21 00:16:08 -04:00
ioprio.c
Kconfig	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2011-05-26 09:52:14 -07:00
Kconfig.binfmt
libfs.c	libfs: drop unneeded dentry_unhash	2011-05-26 07:26:50 -04:00
locks.c	Merge branch 'for-2.6.39' of git://linux-nfs.org/~bfields/linux	2011-03-24 08:20:39 -07:00
Makefile	Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6	2011-03-16 19:01:29 -07:00
mbcache.c	vmscan: change shrinker API by passing shrink_control struct	2011-05-25 08:39:26 -07:00
mpage.c	mm/fs: add hooks to support cleancache	2011-05-26 10:01:43 -06:00
namei.c	Lift the check for automount points into do_lookup()	2011-05-27 07:03:15 -04:00
namespace.c	fs/namespace.c: bound mount propagation fix	2011-05-26 07:26:44 -04:00
nfsctl.c	open-style analog of vfs_path_lookup()	2011-03-14 09:15:28 -04:00
no-block.c
open.c	fs: Use BUG_ON(!mnt) at dentry_open().	2011-03-21 01:10:41 -04:00
pipe.c	Fix broken "pipe: use event aware wakeups" optimization	2011-01-20 16:21:59 -08:00
pnode.c
pnode.h
posix_acl.c	NFS: Prevent memory allocation failure in nfsacl_encode()	2011-01-25 15:24:47 -05:00
read_write.c
read_write.h
readdir.c
select.c	select: remove unused MAX_SELECT_SECONDS	2011-03-21 00:16:08 -04:00
seq_file.c
signalfd.c
splice.c	splice: add wakeup_pipe_readers()	2011-05-23 19:58:53 +02:00
stack.c
stat.c	readlinkat(), fchownat() and fstatat() with empty relative pathnames	2011-03-15 02:21:45 -04:00
statfs.c	clean statfs-like syscalls up	2011-03-14 09:15:28 -04:00
super.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djm/tmem	2011-05-26 10:50:56 -07:00
sync.c	Merge branch 'for-2.6.39/core' of git://git.kernel.dk/linux-2.6-block	2011-03-24 10:16:26 -07:00
timerfd.c	timerfd: Manage cancelable timers in timerfd	2011-05-23 13:59:53 +02:00
utimes.c	userns: rename is_owner_or_cap to inode_owner_or_capable	2011-03-23 19:47:13 -07:00
xattr.c	Cache xattr security drop check for write v2	2011-05-28 12:02:09 -04:00
xattr_acl.c