Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264274AbUDNQ1x (ORCPT ); Wed, 14 Apr 2004 12:27:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264278AbUDNQ1x (ORCPT ); Wed, 14 Apr 2004 12:27:53 -0400 Received: from parcelfarce.linux.theplanet.co.uk ([195.92.249.252]:36992 "EHLO www.linux.org.uk") by vger.kernel.org with ESMTP id S264274AbUDNQ0i (ORCPT ); Wed, 14 Apr 2004 12:26:38 -0400 Date: Wed, 14 Apr 2004 17:26:37 +0100 From: viro@parcelfarce.linux.theplanet.co.uk To: Linus Torvalds Cc: Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: [Patch] BME, noatime and nodiratime Message-ID: <20040414162637.GF31500@parcelfarce.linux.theplanet.co.uk> References: <20040406145544.GA19553@MAIL.13thfloor.at> <20040406204843.GL31500@parcelfarce.linux.theplanet.co.uk> <20040406231136.GN31500@parcelfarce.linux.theplanet.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1524 Lines: 29 On Wed, Apr 14, 2004 at 08:14:18AM -0700, Linus Torvalds wrote: > Ignoring noatime is potentially the only one we should look at, but since > tty's really _are_ "noatime" as far as the filesystem is concerned, I > think it makes sense in the situation we are in anyway. The real reason > for "noatime" is to avoid unnecessary filesystem activity, not that we > necessarily want a constant atime. Another thing we are ignoring is r/o. Oh, well - the same arguments apply. > > 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? > > I don't know about other char drivers, those may well be wrong. But for > tty's in particular, idle time calculations really do pretty much require > the behaviour (apart from #3 - and #3 is, I think, effectively required by > not wanting to touch the disk on keyboard accesses). AFAICS, they simply copy what tty_io.c does. Out of these guys busmouse.c might have a similar excuse; qtronix.c and sonypi.c AFAICS have no reason to touch atime at all. No idea what should usb/core/devio.c do... Anyway, I'm going down right now; expect a patchbomb tonight after I get some sleep... - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/