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From: Gregory Haskins <ghaskins@novell.com>
To: mingo@elte.hu
Cc: rostedt@goodmis.org, ghaskins@novell.com,
	linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH 11/23] Subject: SCHED - Break out the search function
Date: Tue, 04 Dec 2007 15:45:21 -0500	[thread overview]
Message-ID: <20071204204521.3567.2646.stgit@novell1.haskins.net> (raw)
In-Reply-To: <20071204204236.3567.65491.stgit@novell1.haskins.net>

Isolate the search logic into a function so that it can be used later
in places other than find_locked_lowest_rq().

(Checkpatch error is inherited from moved code)

Signed-off-by: Gregory Haskins <ghaskins@novell.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
---

 kernel/sched_rt.c |   66 +++++++++++++++++++++++++++++++----------------------
 1 files changed, 39 insertions(+), 27 deletions(-)

diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index da21c7a..7e26c2c 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -261,54 +261,66 @@ static struct task_struct *pick_next_highest_task_rt(struct rq *rq,
 
 static DEFINE_PER_CPU(cpumask_t, local_cpu_mask);
 
-/* Will lock the rq it finds */
-static struct rq *find_lock_lowest_rq(struct task_struct *task,
-				      struct rq *this_rq)
+static int find_lowest_rq(struct task_struct *task)
 {
-	struct rq *lowest_rq = NULL;
 	int cpu;
-	int tries;
 	cpumask_t *cpu_mask = &__get_cpu_var(local_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 *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 == this_rq->cpu)
-				continue;
+		if (cpu == rq->cpu)
+			continue;
 
-			/* We look for lowest RT prio or non-rt CPU */
-			if (rq->rt.highest_prio >= MAX_RT_PRIO) {
-				lowest_rq = 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 (rq->rt.highest_prio > task->prio &&
-			    (!lowest_rq || rq->rt.highest_prio > lowest_rq->rt.highest_prio)) {
-				lowest_rq = 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;
 
-		if (!lowest_rq)
+	for (tries = 0; tries < RT_MAX_TRIES; tries++) {
+		cpu = find_lowest_rq(task);
+
+		if (cpu == -1)
 			break;
 
+		lowest_rq = cpu_rq(cpu);
+
 		/* if the prio of this runqueue changed, try again */
-		if (double_lock_balance(this_rq, lowest_rq)) {
+		if (double_lock_balance(rq, lowest_rq)) {
 			/*
 			 * We had to unlock the run queue. In
 			 * the mean time, task could have
 			 * migrated already or had its affinity changed.
 			 * Also make sure that it wasn't scheduled on its rq.
 			 */
-			if (unlikely(task_rq(task) != this_rq ||
+			if (unlikely(task_rq(task) != rq ||
 				     !cpu_isset(lowest_rq->cpu, task->cpus_allowed) ||
-				     task_running(this_rq, task) ||
+				     task_running(rq, task) ||
 				     !task->se.on_rq)) {
 				spin_unlock(&lowest_rq->lock);
 				lowest_rq = NULL;


  parent reply	other threads:[~2007-12-04 21:11 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-12-04 20:44 [PATCH 00/23] RT balance v7 Gregory Haskins
2007-12-04 20:44 ` [PATCH 01/23] Subject: SCHED - Add rt_nr_running accounting Gregory Haskins
2007-12-04 20:44 ` [PATCH 02/23] Subject: SCHED - track highest prio queued on runqueue Gregory Haskins
2007-12-04 20:44 ` [PATCH 03/23] Subject: SCHED - push RT tasks Gregory Haskins
2007-12-04 20:44 ` [PATCH 04/23] Subject: SCHED - RT overloaded runqueues accounting Gregory Haskins
2007-12-04 20:44 ` [PATCH 05/23] Subject: SCHED - pull RT tasks Gregory Haskins
2007-12-04 20:44 ` [PATCH 06/23] Subject: SCHED - wake up balance RT Gregory Haskins
2007-12-04 20:45 ` [PATCH 07/23] Subject: SCHED - disable CFS RT load balancing Gregory Haskins
2007-12-04 20:45 ` [PATCH 08/23] Subject: SCHED - Cache cpus_allowed weight for optimizing migration Gregory Haskins
2007-12-04 20:45 ` [PATCH 09/23] Subject: SCHED - Consistency cleanup for this_rq usage Gregory Haskins
2007-12-04 20:45 ` [PATCH 10/23] Subject: SCHED - Remove some CFS specific code from the wakeup path of RT tasks Gregory Haskins
2007-12-04 20:45 ` Gregory Haskins [this message]
2007-12-04 20:45 ` [PATCH 12/23] Subject: SCHED - Allow current_cpu to be included in search Gregory Haskins
2007-12-04 20:45 ` [PATCH 13/23] Subject: SCHED - Pre-route RT tasks on wakeup Gregory Haskins
2007-12-04 20:45 ` [PATCH 14/23] Subject: SCHED - Optimize our cpu selection based on topology Gregory Haskins
2007-12-04 20:45 ` [PATCH 15/23] Subject: SCHED - Optimize rebalancing Gregory Haskins
2007-12-04 20:45 ` [PATCH 16/23] Subject: SCHED - Avoid overload Gregory Haskins
2007-12-04 20:45 ` [PATCH 17/23] Subject: SCHED - restore the migratable conditional Gregory Haskins
2007-12-04 20:45 ` [PATCH 18/23] Subject: SCHED - Optimize cpu search with hamming weight Gregory Haskins
2007-12-04 20:46 ` [PATCH 19/23] Subject: SCHED - Optimize out cpu_clears Gregory Haskins
2007-12-04 20:46 ` [PATCH 20/23] Subject: SCHED - balance RT tasks no new wake up Gregory Haskins
2007-12-04 20:46 ` [PATCH 21/23] Subject: SCHED - Add sched-domain roots Gregory Haskins
2007-12-04 20:46 ` [PATCH 22/23] Subject: SCHED - Only balance our RT tasks within our root-domain Gregory Haskins
2007-12-04 20:46 ` [PATCH 23/23] Subject: SCHED - Use a 2-d bitmap for searching lowest-pri CPU Gregory Haskins
2007-12-04 21:27 ` [PATCH 00/23] RT balance v7 Ingo Molnar
2007-12-04 21:35   ` Gregory Haskins
2007-12-05  2:55   ` [PATCH 0/3] RT balance v7a Gregory Haskins
2007-12-05  2:55     ` [PATCH 1/3] Subject: SCHED - Add sched-domain roots Gregory Haskins
2007-12-05  2:55     ` [PATCH 2/3] Subject: SCHED - Only balance our RT tasks within our root-domain Gregory Haskins
2007-12-05  2:55     ` [PATCH 3/3] Subject: SCHED - Use a 2-d bitmap for searching lowest-pri CPU Gregory Haskins
2007-12-05  9:34       ` Ingo Molnar
2007-12-05 10:19         ` Gregory Haskins
2007-12-05 11:44           ` Ingo Molnar
2007-12-05 13:41             ` Gregory Haskins

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