From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757579Ab0IUClo (ORCPT ); Mon, 20 Sep 2010 22:41:44 -0400 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.125]:47101 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755203Ab0IUClk (ORCPT ); Mon, 20 Sep 2010 22:41:40 -0400 X-Authority-Analysis: v=1.1 cv=GglhOq9PVtWDmzXFaQc2b9ix+3dKCE90LyQFAZ1FxMQ= c=1 sm=0 a=x8wbd8_hBuYA:10 a=bbbx4UPp9XUA:10 a=OPBmh+XkhLl+Enan7BmTLg==:17 a=20KFwNOVAAAA:8 a=1nSz6Ew-AAAA:8 a=meVymXHHAAAA:8 a=oI6s-JDPRIst2FJeducA:9 a=0di-MFiSnOTJN0DHNNmfGm5uG84A:4 a=jEp0ucaQiEUA:10 a=nj4rVwXhlm8A:10 a=jeBq3FmKZ4MA:10 a=OPBmh+XkhLl+Enan7BmTLg==:117 X-Cloudmark-Score: 0 X-Originating-IP: 67.242.120.143 Message-Id: <20100921024138.888922071@goodmis.org> User-Agent: quilt/0.48-1 Date: Mon, 20 Sep 2010 22:40:04 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , Peter Zijlstra , Gregory Haskins , Peter Zijlstra Subject: [PATCH 2/4] sched: Give CPU bound RT tasks preference References: <20100921024002.672817629@goodmis.org> Content-Disposition: inline; filename=0002-sched-Give-CPU-bound-RT-tasks-preference.patch Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Steven Rostedt If a high priority task is waking up on a CPU that is running a lower priority task that is bound to a CPU, see if we can move the high RT task to another CPU first. Note, if all other CPUs are running higher priority tasks than the CPU bounded current task, then it will be preempted regardless. Cc: Peter Zijlstra Cc: Gregory Haskins Signed-off-by: Steven Rostedt --- kernel/sched_rt.c | 8 +++++--- 1 files changed, 5 insertions(+), 3 deletions(-) diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c index 6a02b38..baef30f 100644 --- a/kernel/sched_rt.c +++ b/kernel/sched_rt.c @@ -971,7 +971,8 @@ select_task_rq_rt(struct rq *rq, struct task_struct *p, int sd_flag, int flags) * For equal prio tasks, we just let the scheduler sort it out. */ if (unlikely(rt_task(rq->curr)) && - rq->curr->prio < p->prio && + (rq->curr->rt.nr_cpus_allowed < 2 || + rq->curr->prio < p->prio) && (p->rt.nr_cpus_allowed > 1)) { int cpu = find_lowest_rq(p); @@ -1491,9 +1492,10 @@ static void task_woken_rt(struct rq *rq, struct task_struct *p) if (!task_running(rq, p) && !test_tsk_need_resched(rq->curr) && has_pushable_tasks(rq) && + p->rt.nr_cpus_allowed > 1 && rt_task(rq->curr) && - rq->curr->prio < p->prio && - p->rt.nr_cpus_allowed > 1) + (rq->curr->rt.nr_cpus_allowed < 2 || + rq->curr->prio < p->prio)) push_rt_tasks(rq); } -- 1.7.1