From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753627AbaHKXAY (ORCPT ); Mon, 11 Aug 2014 19:00:24 -0400 Received: from mail-we0-f173.google.com ([74.125.82.173]:47772 "EHLO mail-we0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751593AbaHKXAX (ORCPT ); Mon, 11 Aug 2014 19:00:23 -0400 Date: Tue, 12 Aug 2014 01:00:20 +0200 From: Frederic Weisbecker To: Thomas Gleixner Cc: LKML , Viresh Kumar , Preeti U Murthy Subject: Re: [PATCH 0/2] nohz: Avoid double clock write Message-ID: <20140811230018.GA1492@lerouge> References: <1406825156-11901-1-git-send-email-fweisbec@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1406825156-11901-1-git-send-email-fweisbec@gmail.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Ping? On Thu, Jul 31, 2014 at 06:45:54PM +0200, Frederic Weisbecker wrote: > Hi Thomas, > > The tick reschedules itself unconditionally. That's what we want as long > as the CPU is in periodic mode. It's not that relevant when the CPU > is in dynticks mode though as the clock write is likely to be overwritten > by the nohz code on irq exit. > > In low-res mode, that even result in unexpected periodic behaviour when > no timer is scheduled in the future. > > So here is a set that proposes the removal of these double writes. > > git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git > origin/nohz/drop-double-write-v2 > > Thanks, > Frederic > --- > > Viresh Kumar (2): > nohz: Fix spurious periodic tick behaviour in low-res dynticks mode > nohz: Avoid tick's double reprogramming in highres mode > > > kernel/time/tick-sched.c | 8 ++++++++ > 1 file changed, 8 insertions(+)