linux/fs/kernfs
Ian Kent c7e7c04274 kernfs: use VFS negative dentry caching
If there are many lookups for non-existent paths these negative lookups
can lead to a lot of overhead during path walks.

The VFS allows dentries to be created as negative and hashed, and caches
them so they can be used to reduce the fairly high overhead alloc/free
cycle that occurs during these lookups.

Use the kernfs node parent revision to identify if a change has been
made to the containing directory so that the negative dentry can be
discarded and the lookup redone.

Reviewed-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Ian Kent <raven@themaw.net>
Link: https://lore.kernel.org/r/162642770420.63632.15791924970508867106.stgit@web.messagingengine.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-27 09:29:14 +02:00
..
dir.c kernfs: use VFS negative dentry caching 2021-07-27 09:29:14 +02:00
file.c kernfs: wire up ->splice_read and ->splice_write 2021-01-21 18:30:28 +01:00
inode.c fs: move ramfs_aops to libfs 2021-06-29 10:53:48 -07:00
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
kernfs-internal.h kernfs: add a revision to identify directory node changes 2021-07-27 09:29:14 +02:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
mount.c Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-12-06 09:06:58 -08:00
symlink.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428 2019-06-05 17:37:16 +02:00