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Date:   Tue, 3 Mar 2020 14:14:34 +0100
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Karel Zak <kzak@redhat.com>
Cc:     Miklos Szeredi <miklos@szeredi.hu>,
        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>
Subject: Re: [PATCH 00/17] VFS: Filesystem information and notifications [ver
 #17]
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On Tue, Mar 03, 2020 at 02:03:47PM +0100, Greg Kroah-Hartman wrote:
> On Tue, Mar 03, 2020 at 12:38:14PM +0100, Karel Zak wrote:
> > 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.
> 
> Unlimited beers for a 21-line kernel patch?  Sign me up!
> 
> Totally untested, barely compiled patch below.

Ok, that didn't even build, let me try this for real now...