Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754282Ab1EDQup (ORCPT ); Wed, 4 May 2011 12:50:45 -0400 Received: from e38.co.us.ibm.com ([32.97.110.159]:60093 "EHLO e38.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753941Ab1EDQum (ORCPT ); Wed, 4 May 2011 12:50:42 -0400 Subject: Re: [PATCH] time: Add locking to xtime access in get_seconds() From: Max Asbock To: John Stultz Cc: lkml , John Stultz , Paul Mackerras , "Paul E. McKenney" , Anton Blanchard , Thomas Gleixner In-Reply-To: <1304478708-1273-1-git-send-email-john.stultz@linaro.org> References: <1304478708-1273-1-git-send-email-john.stultz@linaro.org> Content-Type: text/plain Date: Wed, 04 May 2011 09:51:00 -0700 Message-Id: <1304527860.21305.5.camel@w-amax.beaverton.ibm.com> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 670 Lines: 21 On Tue, 2011-05-03 at 20:11 -0700, John Stultz wrote: > From: John Stultz > > So get_seconds() has always been lock free, with the assumption > that accessing a long will be atomic. > get_seconds() is used in the x86 machine check handler and there is a comment saying: /* We hope get_seconds stays lockless */ This needs to be carefully looked at if locking is introduced to get_seconds(). - Max -- 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/