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Date:   Tue, 3 Mar 2020 12:38:14 +0100
From:   Karel Zak <kzak@redhat.com>
To:     Miklos Szeredi <miklos@szeredi.hu>
Cc:     David Howells <dhowells@redhat.com>, Ian Kent <raven@themaw.net>,
        Christian Brauner <christian.brauner@ubuntu.com>,
        James Bottomley <James.Bottomley@hansenpartnership.com>,
        Steven Whitehouse <swhiteho@redhat.com>,
        Miklos Szeredi <mszeredi@redhat.com>,
        viro <viro@zeniv.linux.org.uk>,
        Christian Brauner <christian@brauner.io>,
        Jann Horn <jannh@google.com>,
        "Darrick J. Wong" <darrick.wong@oracle.com>,
        Linux API <linux-api@vger.kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        lkml <linux-kernel@vger.kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Subject: Re: [PATCH 00/17] VFS: Filesystem information and notifications [ver
 #17]
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On Tue, Mar 03, 2020 at 10:26:21AM +0100, Miklos Szeredi wrote:
> No, I don't think this is going to be a performance issue at all, but
> if anything we could introduce a syscall
> 
>   ssize_t readfile(int dfd, const char *path, char *buf, size_t
> bufsize, int flags);

off-topic, but I'll buy you many many beers if you implement it ;-),
because open + read + close is pretty common for /sys and /proc in
many userspace tools; for example ps, top, lsblk, lsmem, lsns, udevd
etc. is all about it.

    Karel

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