---

yaml --- r: 304996 b: refs/heads/master c: 0ce9047 h: refs/heads/master v: v3
git-mirror · May 9, 2012 · 43def9f · 43def9f
1 parent 7960bc9
commit 43def9f
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Showing 4 changed files with 11 additions and 3 deletions.
diff --git a/[refs] b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: c22402a2f76e88b04b7a8b6c0597ad9ba6fd71de
+refs/heads/master: 0ce90475dcdbe90affc218e9688c8401e468e84d
diff --git a/trunk/include/linux/sched.h b/trunk/include/linux/sched.h
@@ -927,6 +927,7 @@ struct sched_group_power {
 struct sched_group {
 	struct sched_group *next;	/* Must be a circular list */
 	atomic_t ref;
+	int balance_cpu;
 
 	unsigned int group_weight;
 	struct sched_group_power *sgp;

diff --git a/trunk/kernel/sched/core.c b/trunk/kernel/sched/core.c
@@ -6060,6 +6060,7 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
 
 		sg->sgp = *per_cpu_ptr(sdd->sgp, cpumask_first(sg_span));
 		atomic_inc(&sg->sgp->ref);
+		sg->balance_cpu = -1;
 
 		if (cpumask_test_cpu(cpu, sg_span))
 			groups = sg;
@@ -6135,6 +6136,7 @@ build_sched_groups(struct sched_domain *sd, int cpu)
 
 		cpumask_clear(sched_group_cpus(sg));
 		sg->sgp->power = 0;
+		sg->balance_cpu = -1;
 
 		for_each_cpu(j, span) {
 			if (get_group(j, sdd, NULL) != group)

diff --git a/trunk/kernel/sched/fair.c b/trunk/kernel/sched/fair.c
@@ -3828,7 +3828,8 @@ static inline void update_sg_lb_stats(struct sched_domain *sd,
 	 */
 	if (local_group) {
 		if (idle != CPU_NEWLY_IDLE) {
-			if (balance_cpu != this_cpu) {
+			if (balance_cpu != this_cpu ||
+			    cmpxchg(&group->balance_cpu, -1, balance_cpu) != -1) {
 				*balance = 0;
 				return;
 			}
@@ -4929,7 +4930,7 @@ static void rebalance_domains(int cpu, enum cpu_idle_type idle)
 	int balance = 1;
 	struct rq *rq = cpu_rq(cpu);
 	unsigned long interval;
-	struct sched_domain *sd;
+	struct sched_domain *sd, *last = NULL;
 	/* Earliest time when we have to do rebalance again */
 	unsigned long next_balance = jiffies + 60*HZ;
 	int update_next_balance = 0;
@@ -4939,6 +4940,7 @@ static void rebalance_domains(int cpu, enum cpu_idle_type idle)
 
 	rcu_read_lock();
 	for_each_domain(cpu, sd) {
+		last = sd;
 		if (!(sd->flags & SD_LOAD_BALANCE))
 			continue;
 
@@ -4983,6 +4985,9 @@ static void rebalance_domains(int cpu, enum cpu_idle_type idle)
 		if (!balance)
 			break;
 	}
+	for (sd = last; sd; sd = sd->child)
+		(void)cmpxchg(&sd->groups->balance_cpu, cpu, -1);
+
 	rcu_read_unlock();
 
 	/*