[Linux-cachefs] Re: [PATCH 30/30] VFS: Destroy the dentries contributed by a superblock on unmounting [try #11]

[Jan Blunck]

On Thu, Jul 27, David Howells wrote:

> diff --git a/include/linux/dcache.h b/include/linux/dcache.h
> index 44605be..63f64a9 100644
> --- a/include/linux/dcache.h
> +++ b/include/linux/dcache.h
> @@ -230,6 +230,7 @@ extern struct dentry * d_alloc_anon(stru
>  extern struct dentry * d_splice_alias(struct inode *, struct dentry *);
>  extern void shrink_dcache_sb(struct super_block *);
>  extern void shrink_dcache_parent(struct dentry *);
> +extern void shrink_dcache_for_umount(struct super_block *);
>  extern int d_invalidate(struct dentry *);
>  
>  /* only used at mount-time */

I don't see the point that we need two different versions of
shrink_dcache_sb(). IMHO it is better to fix shrink_dcache_for_umount() so
that it is a replacement for shrink_dcache_sb().

BTW: Talking about shrink_dcache_sb(): is it really necessary to call
shrink_dcache_sb() when remounting a filesystem? The only reason I can see are
changes to the lookup mechanism (hash algorithm etc) but a quick look into the
different filesystems forbid the change of this options during remount.

Jan