From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1767346AbXDEViJ (ORCPT ); Thu, 5 Apr 2007 17:38:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1767329AbXDEViI (ORCPT ); Thu, 5 Apr 2007 17:38:08 -0400 Received: from e33.co.us.ibm.com ([32.97.110.151]:57604 "EHLO e33.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1767348AbXDEViH (ORCPT ); Thu, 5 Apr 2007 17:38:07 -0400 Subject: Re: [PATCH] timekeeping: drop irq-context clocksource polling From: john stultz To: Daniel Walker Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org, mingo@elte.hu In-Reply-To: <1175808567.15973.137.camel@imap.mvista.com> References: <20070405210316.785839431@mvista.com> <1175808319.28526.26.camel@localhost> <1175808567.15973.137.camel@imap.mvista.com> Content-Type: text/plain Date: Thu, 05 Apr 2007 14:38:02 -0700 Message-Id: <1175809082.28526.28.camel@localhost> Mime-Version: 1.0 X-Mailer: Evolution 2.8.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2007-04-05 at 14:29 -0700, Daniel Walker wrote: > On Thu, 2007-04-05 at 14:25 -0700, john stultz wrote: > > On Thu, 2007-04-05 at 14:03 -0700, Daniel Walker wrote: > > > Before this change the timekeeping code would poll the clocksource > > > list every interrupt. This changes that so the clocksource list is > > > only checked when there has been and update, and no longer checks > > > in interrupt context. > > > > > > This also has a few small space and line cleanups. > > > > > > Boot tested on i386, compile tested on x86_64 .. However, I couldn't > > > find a !GENERIC_TIME that compiled without this change so it's untested.. > > > > > > Signed-Off-By: Daniel Walker > > > > Err.. I think you need to be holding a write on the xtime_lock (as is > > done before calling update_wall_time()) when changing the clocksource. > > I added a write_seqlock_irqsave() on xtime_lock in > change_clocksource() .. Did I need more (different) protection than > that? Nope. You're ok there. I just missed it and then I tried to cancel my mail from being sent, but apparently it still got out. whoops! :) -john