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	Sun, 05 Nov 2023 21:59:46 +0000
Date: Sun, 5 Nov 2023 21:59:46 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-fsdevel@vger.kernel.org
Subject: Re: [RFC] simplifying fast_dput(), dentry_kill() et.al.
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Sun, Nov 05, 2023 at 07:54:16PM +0000, Al Viro wrote:

> 	* have shrink_dcache_for_umount() mark the superblock (either in
> ->s_flags or inside the ->s_dentry_lru itself) and have the logics
> in retain_dentry() that does insertion into LRU list check ->d_sb for that
> mark, treating its presence as "do not retain".

	BTW, no barriers, etc. are needed for those - once we are into
shrink_dentry_for_umount() there must be no dput() calls anywhere on
that filesystem.