From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754430Ab2DSIaG (ORCPT ); Thu, 19 Apr 2012 04:30:06 -0400 Received: from www.linutronix.de ([62.245.132.108]:38027 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753946Ab2DSIaB (ORCPT ); Thu, 19 Apr 2012 04:30:01 -0400 Date: Thu, 19 Apr 2012 10:29:46 +0200 (CEST) From: Thomas Gleixner To: Suresh Siddha cc: Santosh Shilimkar , mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, svenjoac@gmx.de, rjw@sisk.pl, linux-tip-commits@vger.kernel.org Subject: Re: [tip:timers/urgent] tick: Fix oneshot broadcast setup really In-Reply-To: <1334802459.28674.209.camel@sbsiddha-desk.sc.intel.com> Message-ID: References: <4F8ECD39.3080900@ti.com> <1334802459.28674.209.camel@sbsiddha-desk.sc.intel.com> User-Agent: Alpine 2.02 (LFD 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 18 Apr 2012, Suresh Siddha wrote: > On Wed, 2012-04-18 at 17:31 +0200, Thomas Gleixner wrote: > From: Suresh Siddha > Subject: tick: Fix the spurious broadcast timer ticks > > During resume, tick_resume_broadcast() programs the broadcast timer > in oneshot mode unconditionally. On the platforms where broadcast timer > is not really required, this will generate spurious broadcast timer ticks > upon resume. For example, on the always running apic timer platforms with > HPET, I see spurious hpet tick once every ~5minutes (which is the 32-bit > hpet counter wraparound time). > > Similar to boot time, during resume make the oneshot mode setting of > the broadcast clock event device conditional on the state of active broadcast > users. > > Signed-off-by: Suresh Siddha Sven, Santosh, can you confirm that this works for you on top of the other two patches? > --- > kernel/time/tick-broadcast.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c > index bf57abd..766cd82 100644 > --- a/kernel/time/tick-broadcast.c > +++ b/kernel/time/tick-broadcast.c > @@ -346,7 +346,8 @@ int tick_resume_broadcast(void) > tick_get_broadcast_mask()); > break; > case TICKDEV_MODE_ONESHOT: > - broadcast = tick_resume_broadcast_oneshot(bc); > + if (!cpumask_empty(tick_get_broadcast_mask())) > + broadcast = tick_resume_broadcast_oneshot(bc); > break; > } > } > > >