From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759785Ab2J2UjO (ORCPT ); Mon, 29 Oct 2012 16:39:14 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:2176 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758309Ab2J2Uiz (ORCPT ); Mon, 29 Oct 2012 16:38:55 -0400 X-Authority-Analysis: v=2.0 cv=dvhZ+ic4 c=1 sm=0 a=rXTBtCOcEpjy1lPqhTCpEQ==:17 a=mNMOxpOpBa8A:10 a=Ciwy3NGCPMMA:10 a=uaG8WcV_eN8A:10 a=5SG0PmZfjMsA:10 a=bbbx4UPp9XUA:10 a=meVymXHHAAAA:8 a=xMB5LTxmEmUA:10 a=pGLkceISAAAA:8 a=VwQbUJbxAAAA:8 a=Z4Rwk6OoAAAA:8 a=20KFwNOVAAAA:8 a=9AzMRrQhAAAA:8 a=NufY4J3AAAAA:8 a=KKAkSRfTAAAA:8 a=JfrnYn6hAAAA:8 a=ftUzEednAAAA:8 a=sozttTNsAAAA:8 a=EUspDBNiAAAA:8 a=VnNF1IyMAAAA:8 a=fh4mg5NFAAAA:8 a=qrV5slhodKc-BZKJUhwA:9 a=MSl-tDqOz04A:10 a=LI9Vle30uBYA:10 a=jbrJJM5MRmoA:10 a=jEp0ucaQiEUA:10 a=SxxB86fLhQ4A:10 a=re9sYKne76oA:10 a=WwgC8nHKvroA:10 a=3Rfx1nUSh_UA:10 a=QwxQZocgbLcA:10 a=x2szoZtqnggA:10 a=IG2fH9E8heMA:10 a=Im-eZXwrtqoA:10 a=jeBq3FmKZ4MA:10 a=Zh68SRI7RUMA:10 a=rXTBtCOcEpjy1lPqhTCpEQ==:117 X-Cloudmark-Score: 0 X-Originating-IP: 74.67.115.198 Message-Id: <20121029203849.877581251@goodmis.org> User-Agent: quilt/0.60-1 Date: Mon, 29 Oct 2012 16:27:33 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Andrew Morton , Thomas Gleixner , Peter Zijlstra , Clark Williams , Frederic Weisbecker , Li Zefan , Ingo Molnar , "Paul E. McKenney" , Mike Galbraith , Alessio Igor Bogani , Avi Kivity , Chris Metcalf , Christoph Lameter , Daniel Lezcano , Geoff Levand , Gilad Ben Yossef , Hakan Akkan , Kevin Hilman , Max Krasnyansky , Stephen Hemminger , Sven-Thorsten Dietrich Subject: [PATCH 22/32] sched: Comment on rq->clock correctness in ttwu_do_wakeup() in nohz References: <20121029202711.062749374@goodmis.org> Content-Disposition: inline; filename=0022-sched-Comment-on-rq-clock-correctness-in-ttwu_do_wak.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Frederic Weisbecker Signed-off-by: Frederic Weisbecker Cc: Alessio Igor Bogani Cc: Andrew Morton Cc: Avi Kivity Cc: Chris Metcalf Cc: Christoph Lameter Cc: Daniel Lezcano Cc: Geoff Levand Cc: Gilad Ben Yossef Cc: Hakan Akkan Cc: Ingo Molnar Cc: Kevin Hilman Cc: Max Krasnyansky Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Stephen Hemminger Cc: Steven Rostedt Cc: Sven-Thorsten Dietrich Cc: Thomas Gleixner --- kernel/sched/core.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index bebea17..783d5e4 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1309,6 +1309,12 @@ ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags) if (p->sched_class->task_woken) p->sched_class->task_woken(rq, p); + /* + * For adaptive nohz case: We called ttwu_activate() + * which just updated the rq clock. There is an + * exception with p->on_rq != 0 but in this case + * we are not idle and rq->idle_stamp == 0 + */ if (rq->idle_stamp) { u64 delta = rq->clock - rq->idle_stamp; u64 max = 2*sysctl_sched_migration_cost; -- 1.7.10.4