From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756543AbXKFAuo (ORCPT ); Mon, 5 Nov 2007 19:50:44 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754608AbXKFAud (ORCPT ); Mon, 5 Nov 2007 19:50:33 -0500 Received: from nds154-200.nds.lab.novell.com ([151.155.154.200]:25181 "EHLO lsg.lab.novell.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750950AbXKFAuc (ORCPT ); Mon, 5 Nov 2007 19:50:32 -0500 X-Greylist: delayed 2000 seconds by postgrey-1.27 at vger.kernel.org; Mon, 05 Nov 2007 19:50:32 EST From: Gregory Haskins Subject: [PATCH 3/8] RT: Break out the search function To: rostedt@goodmis.org Cc: mingo@elte.hu, dvhltc@us.ibm.com, zijlstra@redhat.com, linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org, ghaskins@novell.com Date: Mon, 05 Nov 2007 16:48:48 -0700 Message-ID: <20071105234847.25451.6571.stgit@lsg> In-Reply-To: <20071105234832.25451.55430.stgit@lsg> References: <20071105234832.25451.55430.stgit@lsg> User-Agent: StGIT/0.12.1 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Isolate the search logic into a function so that it can be used later in places other than find_locked_lowest_rq(). Signed-off-by: Gregory Haskins --- kernel/sched_rt.c | 62 ++++++++++++++++++++++++++++++++--------------------- 1 files changed, 37 insertions(+), 25 deletions(-) diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c index f1fc1b4..fbe7b8a 100644 --- a/kernel/sched_rt.c +++ b/kernel/sched_rt.c @@ -312,43 +312,55 @@ static struct task_struct *pick_next_highest_task_rt(struct rq *rq, return next; } -/* Will lock the rq it finds */ -static struct rq *find_lock_lowest_rq(struct task_struct *task, - struct rq *rq) +static int find_lowest_rq(struct task_struct *task) { - struct rq *lowest_rq = NULL; - cpumask_t cpu_mask; int cpu; - int tries; + cpumask_t cpu_mask; + struct rq *lowest_rq = NULL; cpus_and(cpu_mask, cpu_online_map, task->cpus_allowed); - for (tries = 0; tries < RT_MAX_TRIES; tries++) { - /* - * Scan each rq for the lowest prio. - */ - for_each_cpu_mask(cpu, cpu_mask) { - struct rq *curr_rq = &per_cpu(runqueues, cpu); + /* + * Scan each rq for the lowest prio. + */ + for_each_cpu_mask(cpu, cpu_mask) { + struct rq *rq = cpu_rq(cpu); - if (cpu == rq->cpu) - continue; + if (cpu == rq->cpu) + continue; - /* We look for lowest RT prio or non-rt CPU */ - if (curr_rq->rt.highest_prio >= MAX_RT_PRIO) { - lowest_rq = curr_rq; - break; - } + /* We look for lowest RT prio or non-rt CPU */ + if (rq->rt.highest_prio >= MAX_RT_PRIO) { + lowest_rq = rq; + break; + } - /* no locking for now */ - if (curr_rq->rt.highest_prio > task->prio && - (!lowest_rq || curr_rq->rt.highest_prio > lowest_rq->rt.highest_prio)) { - lowest_rq = curr_rq; - } + /* no locking for now */ + if (rq->rt.highest_prio > task->prio && + (!lowest_rq || rq->rt.highest_prio > lowest_rq->rt.highest_prio)) { + lowest_rq = rq; } + } + + return lowest_rq ? lowest_rq->cpu : -1; +} + +/* Will lock the rq it finds */ +static struct rq *find_lock_lowest_rq(struct task_struct *task, + struct rq *rq) +{ + struct rq *lowest_rq = NULL; + int cpu; + int tries; + + for (tries = 0; tries < RT_MAX_TRIES; tries++) { + cpu = find_lowest_rq(task); - if (!lowest_rq) + if (cpu == -1) break; + lowest_rq = cpu_rq(cpu); + /* if the prio of this runqueue changed, try again */ if (double_lock_balance(rq, lowest_rq)) { /*