On Tue, 15 Jun 2021 at 12:26, Ian Kent <raven@xxxxxxxxxx> wrote: > > 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. > > Signed-off-by: Ian Kent <raven@xxxxxxxxxx> Reviewed-by: Miklos Szeredi <mszeredi@xxxxxxxxxx>
