From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756082AbdJJLAG (ORCPT ); Tue, 10 Oct 2017 07:00:06 -0400 Received: from terminus.zytor.com ([65.50.211.136]:41643 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755344AbdJJLAF (ORCPT ); Tue, 10 Oct 2017 07:00:05 -0400 Date: Tue, 10 Oct 2017 03:56:12 -0700 From: tip-bot for Luca Abeni Message-ID: Cc: bristot@redhat.com, peterz@infradead.org, mathieu.poirier@linaro.org, linux-kernel@vger.kernel.org, hpa@zytor.com, efault@gmx.de, mingo@kernel.org, juri.lelli@arm.com, rostedt@goodmis.org, tglx@linutronix.de, luca.abeni@santannapisa.it, torvalds@linux-foundation.org Reply-To: juri.lelli@arm.com, mingo@kernel.org, efault@gmx.de, rostedt@goodmis.org, tglx@linutronix.de, torvalds@linux-foundation.org, luca.abeni@santannapisa.it, bristot@redhat.com, mathieu.poirier@linaro.org, peterz@infradead.org, linux-kernel@vger.kernel.org, hpa@zytor.com In-Reply-To: <1504778971-13573-3-git-send-email-luca.abeni@santannapisa.it> References: <1504778971-13573-3-git-send-email-luca.abeni@santannapisa.it> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] sched/deadline: Fix switching to -deadline Git-Commit-ID: 295d6d5e373607729bcc8182c25afe964655714f 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: 295d6d5e373607729bcc8182c25afe964655714f Gitweb: https://git.kernel.org/tip/295d6d5e373607729bcc8182c25afe964655714f Author: Luca Abeni AuthorDate: Thu, 7 Sep 2017 12:09:29 +0200 Committer: Ingo Molnar CommitDate: Tue, 10 Oct 2017 11:43:30 +0200 sched/deadline: Fix switching to -deadline Fix a bug introduced in: 72f9f3fdc928 ("sched/deadline: Remove dl_new from struct sched_dl_entity") After that commit, when switching to -deadline if the scheduling deadline of a task is in the past then switched_to_dl() calls setup_new_entity() to properly initialize the scheduling deadline and runtime. The problem is that the task is enqueued _before_ having its parameters initialized by setup_new_entity(), and this can cause problems. For example, a task with its out-of-date deadline in the past will potentially be enqueued as the highest priority one; however, its adjusted deadline may not be the earliest one. This patch fixes the problem by initializing the task's parameters before enqueuing it. Signed-off-by: luca abeni Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Daniel Bristot de Oliveira Cc: Juri Lelli Cc: Linus Torvalds Cc: Mathieu Poirier Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1504778971-13573-3-git-send-email-luca.abeni@santannapisa.it Signed-off-by: Ingo Molnar --- kernel/sched/deadline.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 0191ec7..9d45354 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1364,6 +1364,10 @@ enqueue_dl_entity(struct sched_dl_entity *dl_se, update_dl_entity(dl_se, pi_se); } else if (flags & ENQUEUE_REPLENISH) { replenish_dl_entity(dl_se, pi_se); + } else if ((flags & ENQUEUE_RESTORE) && + dl_time_before(dl_se->deadline, + rq_clock(rq_of_dl_rq(dl_rq_of_se(dl_se))))) { + setup_new_dl_entity(dl_se); } __enqueue_dl_entity(dl_se); @@ -2255,13 +2259,6 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p) return; } - /* - * If p is boosted we already updated its params in - * rt_mutex_setprio()->enqueue_task(..., ENQUEUE_REPLENISH), - * p's deadline being now already after rq_clock(rq). - */ - if (dl_time_before(p->dl.deadline, rq_clock(rq))) - setup_new_dl_entity(&p->dl); if (rq->curr != p) { #ifdef CONFIG_SMP