From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934015AbbBDOfm (ORCPT ); Wed, 4 Feb 2015 09:35:42 -0500 Received: from terminus.zytor.com ([198.137.202.10]:38697 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932981AbbBDOfj (ORCPT ); Wed, 4 Feb 2015 09:35:39 -0500 Date: Wed, 4 Feb 2015 06:34:52 -0800 From: tip-bot for Wanpeng Li Message-ID: Cc: peterz@infradead.org, wanpeng.li@linux.intel.com, mingo@kernel.org, hpa@zytor.com, torvalds@linux-foundation.org, tglx@linutronix.de, ktkhai@parallels.com, linux-kernel@vger.kernel.org, juri.lelli@arm.com Reply-To: wanpeng.li@linux.intel.com, mingo@kernel.org, peterz@infradead.org, juri.lelli@arm.com, ktkhai@parallels.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, torvalds@linux-foundation.org, hpa@zytor.com In-Reply-To: <1416962647-76792-2-git-send-email-wanpeng.li@linux.intel.com> References: <1416962647-76792-2-git-send-email-wanpeng.li@linux.intel.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] sched/deadline: Fix hrtick for a non-leftmost task Git-Commit-ID: a7bebf488791aa1036f3e6629daf01d01f705dcb 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 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: a7bebf488791aa1036f3e6629daf01d01f705dcb Gitweb: http://git.kernel.org/tip/a7bebf488791aa1036f3e6629daf01d01f705dcb Author: Wanpeng Li AuthorDate: Wed, 26 Nov 2014 08:44:01 +0800 Committer: Ingo Molnar CommitDate: Wed, 4 Feb 2015 07:52:25 +0100 sched/deadline: Fix hrtick for a non-leftmost task After update_curr_dl() the current task might not be the leftmost task anymore. In that case do not start a new hrtick for it. In this case NEED_RESCHED will be set and the next schedule will start the hrtick for the new task if and when appropriate. Signed-off-by: Wanpeng Li Acked-by: Juri Lelli [ Rewrote the changelog and comment. ] Signed-off-by: Peter Zijlstra (Intel) Cc: Kirill Tkhai Cc: Linus Torvalds Link: http://lkml.kernel.org/r/1416962647-76792-2-git-send-email-wanpeng.li@linux.intel.com Signed-off-by: Ingo Molnar --- kernel/sched/deadline.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index e0e9c29..7b684f9 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1073,7 +1073,13 @@ static void task_tick_dl(struct rq *rq, struct task_struct *p, int queued) { update_curr_dl(rq); - if (hrtick_enabled(rq) && queued && p->dl.runtime > 0) + /* + * Even when we have runtime, update_curr_dl() might have resulted in us + * not being the leftmost task anymore. In that case NEED_RESCHED will + * be set and schedule() will start a new hrtick for the next task. + */ + if (hrtick_enabled(rq) && queued && p->dl.runtime > 0 && + is_leftmost(p, &rq->dl)) start_hrtick_dl(rq, p); }