Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933747AbZIDQai (ORCPT ); Fri, 4 Sep 2009 12:30:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932747AbZIDQaf (ORCPT ); Fri, 4 Sep 2009 12:30:35 -0400 Received: from cavan.codon.org.uk ([93.93.128.6]:46079 "EHLO cavan.codon.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754451AbZIDQae (ORCPT ); Fri, 4 Sep 2009 12:30:34 -0400 Date: Fri, 4 Sep 2009 17:30:29 +0100 From: Matthew Garrett To: Alessandro Zummo Cc: rtc-linux@googlegroups.com, linux-kernel@vger.kernel.org Subject: Re: [rtc-linux] [PATCH 2/2] rtc: Add boot_timesource sysfs attribute Message-ID: <20090904163029.GA25239@srcf.ucam.org> References: <1252081568-6000-1-git-send-email-mjg@redhat.com> <1252081568-6000-2-git-send-email-mjg@redhat.com> <20090904182528.591dbd29@i1501.lan.towertech.it> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090904182528.591dbd29@i1501.lan.towertech.it> User-Agent: Mutt/1.5.18 (2008-05-17) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: mjg59@cavan.codon.org.uk X-SA-Exim-Scanned: No (on cavan.codon.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 917 Lines: 22 On Fri, Sep 04, 2009 at 06:25:28PM +0200, Alessandro Zummo wrote: > This feature is meant to be in addition of the regular > hwclock call to read the system time. > > Have you tested if there are drawbacks by not reading it? Like > TZ, DST and similar? Current util-linux has a hwclock that can just set the timezone without performing a full read. However, there's no way of knowing whether it's safe to do this without knowing that the kernel config option was set and used. We'd prefer to avoid always doing --hctosys because it's a noticable performance hit on boot if the work's already been done by the kernel. -- Matthew Garrett | mjg59@srcf.ucam.org -- 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/