From ac90ebfb20fa3eb4edcf2ad57d73e533468e2f81 Mon Sep 17 00:00:00 2001
From: Nick Piggin <nickpiggin@yahoo.com.au>
Date: Sat, 25 Jun 2005 14:57:30 -0700
Subject: [PATCH] --- yaml --- r: 3301 b: refs/heads/master c:
 77391d71681d05d2f4502f91ad62618522abf624 h: refs/heads/master i:   3299:
 b1e50c9c3c2dd3c373090cd667e083603e21f8dd v: v3

---
 [refs]               |  2 +-
 trunk/kernel/sched.c | 11 +++++++++--
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 29f72ab9def9..f0919f1c67a8 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 476d139c218e44e045e4bc6d4cc02b010b343939
+refs/heads/master: 77391d71681d05d2f4502f91ad62618522abf624
diff --git a/trunk/kernel/sched.c b/trunk/kernel/sched.c
index 579da278e72f..6e452eb95ac3 100644
--- a/trunk/kernel/sched.c
+++ b/trunk/kernel/sched.c
@@ -2030,6 +2030,12 @@ static runqueue_t *find_busiest_queue(struct sched_group *group)
 	return busiest;
 }
 
+/*
+ * Max backoff if we encounter pinned tasks. Pretty arbitrary value, but
+ * so long as it is large enough.
+ */
+#define MAX_PINNED_INTERVAL	512
+
 /*
  * Check this_cpu to ensure it is balanced within domain. Attempt to move
  * tasks if there is an imbalance.
@@ -2042,7 +2048,7 @@ static int load_balance(int this_cpu, runqueue_t *this_rq,
 	struct sched_group *group;
 	runqueue_t *busiest;
 	unsigned long imbalance;
-	int nr_moved, all_pinned;
+	int nr_moved, all_pinned = 0;
 	int active_balance = 0;
 
 	spin_lock(&this_rq->lock);
@@ -2133,7 +2139,8 @@ static int load_balance(int this_cpu, runqueue_t *this_rq,
 
 	sd->nr_balance_failed = 0;
 	/* tune up the balancing interval */
-	if (sd->balance_interval < sd->max_interval)
+	if ((all_pinned && sd->balance_interval < MAX_PINNED_INTERVAL) ||
+			(sd->balance_interval < sd->max_interval))
 		sd->balance_interval *= 2;
 
 	return 0;