From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754559Ab2BOTh5 (ORCPT ); Wed, 15 Feb 2012 14:37:57 -0500 Received: from terminus.zytor.com ([198.137.202.10]:53062 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752170Ab2BOThy (ORCPT ); Wed, 15 Feb 2012 14:37:54 -0500 Date: Wed, 15 Feb 2012 11:36:53 -0800 From: tip-bot for Suresh Siddha Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, johnstul@us.ibm.com, suresh.b.siddha@intel.com, tglx@linutronix.de Reply-To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, johnstul@us.ibm.com, suresh.b.siddha@intel.com, tglx@linutronix.de In-Reply-To: <1320452301.15071.16.camel@sbsiddha-desk.sc.intel.com> References: <1320452301.15071.16.camel@sbsiddha-desk.sc.intel.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:timers/core] clockevents: Leave the broadcast device in shutdown mode when not needed Git-Commit-ID: 77b0d60c5adf39c74039e2142a1d3cd1e4d53799 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.6 (terminus.zytor.com [127.0.0.1]); Wed, 15 Feb 2012 11:37:33 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 77b0d60c5adf39c74039e2142a1d3cd1e4d53799 Gitweb: http://git.kernel.org/tip/77b0d60c5adf39c74039e2142a1d3cd1e4d53799 Author: Suresh Siddha AuthorDate: Fri, 4 Nov 2011 17:18:21 -0700 Committer: Thomas Gleixner CommitDate: Wed, 15 Feb 2012 15:23:09 +0100 clockevents: Leave the broadcast device in shutdown mode when not needed Platforms with Always Running APIC Timer doesn't use the broadcast timer but the kernel is leaving the broadcast timer (HPET in this case) in oneshot mode. On these platforms, before the switch to oneshot mode, broadcast device is actually in shutdown mode. Code checks for empty tick_broadcast_mask and avoids going into the periodic mode. During switch to oneshot mode, add the same tick_broadcast_mask checks in the tick_broadcast_switch_to_oneshot() and avoid the broadcast device going into the oneshot mode. Signed-off-by: Suresh Siddha Cc: john stultz Cc: venki@google.com Link: http://lkml.kernel.org/r/1320452301.15071.16.camel@sbsiddha-desk.sc.intel.com Signed-off-by: Thomas Gleixner --- kernel/time/tick-broadcast.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index fd4a7b1..e883f57 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -575,11 +575,15 @@ void tick_broadcast_switch_to_oneshot(void) unsigned long flags; raw_spin_lock_irqsave(&tick_broadcast_lock, flags); + if (cpumask_empty(tick_get_broadcast_mask())) + goto end; tick_broadcast_device.mode = TICKDEV_MODE_ONESHOT; bc = tick_broadcast_device.evtdev; if (bc) tick_broadcast_setup_oneshot(bc); + +end: raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags); }