Date: Wed, 7 Apr 2004 00:11:36 +0100
From: viro@parcelfarce.linux.theplanet.co.uk
To: Andrew Morton <akpm@osdl.org>, torvalds@osdl.org,
       linux-kernel@vger.kernel.org
Subject: Re: [Patch] BME, noatime and nodiratime
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On Tue, Apr 06, 2004 at 09:48:44PM +0100, viro@parcelfarce.linux.theplanet.co.uk wrote:

> noatime/nodiratime: OK, but we still have direct modifications of i_atime
> that need to be taken care of.

Particulary interesting one is in tty_io.c.  There we
	1) unconditionally touch i_atime on read()
	2) do not touch it on write()
	3) never mark the inode dirty.

Note that the last one means that doing stat() in a loop will sometimes
give atime going backwards.  We also completely ignore noatime here.

There are similar places in some other char drivers.  Obvious step would
be to have them do file_accessed() instead; however, I'd really like to
hear the rationale for existing behaviour.  Comments?
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