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Date:   Fri, 3 Apr 2020 11:11:24 +0200
From:   Karel Zak <kzak@redhat.com>
To:     Miklos Szeredi <miklos@szeredi.hu>
Cc:     David Howells <dhowells@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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On Wed, Apr 01, 2020 at 05:25:54PM +0200, Miklos Szeredi wrote:
> fsinfo(2) will never be substantially cheaper than reading and parsing
> /mnt/MNT_ID/info.  In fact reading a large part of the mount table
> using fsinfo(2) will be substantially slower than parsing
> /proc/self/mountinfo (this doesn't actually do the parsing but that
> would add a very small amount of overhead):

I think nobody wants to use fsinfo() or mountfs as replacement to whole
/proc/self/mountinfo. It does not make sense. We need per-mountpoint
API, for whole mount table use-cases (like findmnt or lsblk) the
current mountinfo is good enough.

    Karel

-- 
 Karel Zak  <kzak@redhat.com>
 http://karelzak.blogspot.com