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From:   David Howells <dhowells@redhat.com>
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Cc:     dhowells@redhat.com, Miklos Szeredi <miklos@szeredi.hu>,
        Karel Zak <kzak@redhat.com>,
        Christian Brauner <christian.brauner@ubuntu.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Al Viro <viro@zeniv.linux.org.uk>, dray@redhat.com,
        Miklos Szeredi <mszeredi@redhat.com>,
        Steven Whitehouse <swhiteho@redhat.com>,
        Jeff Layton <jlayton@redhat.com>, Ian Kent <raven@themaw.net>,
        andres@anarazel.de, keyrings@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        Lennart Poettering <lennart@poettering.net>,
        Aleksa Sarai <cyphar@cyphar.com>
Subject: Re: Upcoming: Notifications, FS notifications and fsinfo()
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Date:   Wed, 01 Apr 2020 14:58:22 +0100
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David Howells <dhowells@redhat.com> wrote:

> > Attached patch applies against readfile patch.
> =

> But doesn't actually do what Karel asked for.  show_mountinfo() itself d=
oes
> not give you what Karel asked for.  Plus there's more information you ne=
ed to
> add to it.

And arguably, it's worse than just reading /proc/mounts.  If you get a
notification that something changed (ie. you poll /proc/mounts or mount
notifications gives you an overrun) you now have to read *every*
/mountfs/*/info file.  That is way more expensive.

David