Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750725AbWJBKUR (ORCPT ); Mon, 2 Oct 2006 06:20:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750733AbWJBKUQ (ORCPT ); Mon, 2 Oct 2006 06:20:16 -0400 Received: from main.gmane.org ([80.91.229.2]:54155 "EHLO ciao.gmane.org") by vger.kernel.org with ESMTP id S1750725AbWJBKUP (ORCPT ); Mon, 2 Oct 2006 06:20:15 -0400 X-Injected-Via-Gmane: http://gmane.org/ To: linux-kernel@vger.kernel.org From: Samuel Tardieu Subject: Re: How is Code in do_sys_settimeofday() safe in case of SMP and Nest Kernel Path? Date: 02 Oct 2006 12:12:34 +0200 Message-ID: <87hcynm3fx.fsf@willow.rfc1149.net> References: <451E8143.5030300@yahoo.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Complaints-To: usenet@sea.gmane.org X-Gmane-NNTP-Posting-Host: zaphod.rfc1149.net User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.4 X-Leafnode-NNTP-Posting-Host: 2001:6f8:37a:2::2 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 883 Lines: 15 >>>>> "Christoph" == Christoph Lameter writes: Christoph> I really hate adding overhead to gettimeofday() and we Christoph> would have to take the seqlock in all places when we Christoph> reference tz. Maybe we can tolerate the resulting race? Agreed. In some applications, gettimeofday() is called an awfully lot of times. And the only plausible case where settimeofday() is called after boot is on a multi-core laptop during a traval accross different timezones, where it is unlikely that time-and-DST-sensitive applications would be running. Sam -- Samuel Tardieu -- sam@rfc1149.net -- http://www.rfc1149.net/ - 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/