From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail333.us4.mandrillapp.com ([205.201.137.77]:39883 "EHLO mail333.us4.mandrillapp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752285AbcCAWAx (ORCPT ); Tue, 1 Mar 2016 17:00:53 -0500 Received: from pmta03.dal05.mailchimp.com (127.0.0.1) by mail333.us4.mandrillapp.com id hqo8ha174nod for ; Tue, 1 Mar 2016 22:00:52 +0000 (envelope-from ) From: Subject: Patch "tick/nohz: Set the correct expiry when switching to nohz/lowres mode" has been added to the 4.4-stable tree To: , , , , , Cc: , Message-Id: <145686964810851@kroah.com> Date: Tue, 01 Mar 2016 22:00:51 +0000 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled tick/nohz: Set the correct expiry when switching to nohz/lowres mode to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: tick-nohz-set-the-correct-expiry-when-switching-to-nohz-lowres-mode.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 1ca8ec532fc2d986f1f4a319857bb18e0c9739b4 Mon Sep 17 00:00:00 2001 From: Wanpeng Li Date: Wed, 27 Jan 2016 19:26:07 +0800 Subject: tick/nohz: Set the correct expiry when switching to nohz/lowres mode From: Wanpeng Li commit 1ca8ec532fc2d986f1f4a319857bb18e0c9739b4 upstream. commit 0ff53d096422 sets the next tick interrupt to the last jiffies update, i.e. in the past, because the forward operation is invoked before the set operation. There is no resulting damage (yet), but we get an extra pointless tick interrupt. Revert the order so we get the next tick interrupt in the future. Fixes: commit 0ff53d096422 "tick: sched: Force tick interrupt and get rid of softirq magic" Signed-off-by: Wanpeng Li Cc: Peter Zijlstra Cc: Frederic Weisbecker Link: http://lkml.kernel.org/r/1453893967-3458-1-git-send-email-wanpeng.li@hotmail.com Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman --- kernel/time/tick-sched.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -977,9 +977,9 @@ static void tick_nohz_switch_to_nohz(voi /* Get the next period */ next = tick_init_jiffy_update(); - hrtimer_forward_now(&ts->sched_timer, tick_period); hrtimer_set_expires(&ts->sched_timer, next); - tick_program_event(next, 1); + hrtimer_forward_now(&ts->sched_timer, tick_period); + tick_program_event(hrtimer_get_expires(&ts->sched_timer), 1); tick_nohz_activate(ts, NOHZ_MODE_LOWRES); } Patches currently in stable-queue which might be from kernellwp@gmail.com are queue-4.4/tick-nohz-set-the-correct-expiry-when-switching-to-nohz-lowres-mode.patch