[PATCH 4/5] scheduler: Add boot time enabling/disabling of cluster scheduling

[Tim Chen <tim.c.chen@linux.intel.com>]

Add boot time parameter sched_cluster to enable or disable cluster
scheduling.  Set boot parameter as follow:

	sched_cluster=0 disables cluster scheduling
	sched_cluster=1 enables cluster scheduling

Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
---
 Documentation/admin-guide/kernel-parameters.txt |  4 ++++
 kernel/sched/topology.c                         | 16 ++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 9725c546a0d4..40ad997430e1 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -5023,6 +5023,10 @@
 
 	sched_verbose	[KNL] Enables verbose scheduler debug messages.
 
+	sched_cluster=  Enable or disable cluster scheduling.
+			0 -- disable.
+			1 -- enable.
+
 	schedstats=	[KNL,X86] Enable or disable scheduled statistics.
 			Allowed values are enable and disable. This feature
 			incurs a small amount of overhead in the scheduler
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c
index e362bba29f95..087854d505f7 100644
--- a/kernel/sched/topology.c
+++ b/kernel/sched/topology.c
@@ -1697,6 +1697,22 @@ int sched_cluster_handler(struct ctl_table *table, int write,
 
 	return ret;
 }
+
+static int __init sched_cluster_option(char *str)
+{
+	int enable;
+
+	if (get_option(&str, &enable)) {
+		if (enable != 0 && enable != 1)
+			return -EINVAL;
+
+		sysctl_sched_cluster = enable;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+early_param("sched_cluster", sched_cluster_option);
 #endif
 
 static struct sched_domain_topology_level *next_tl(struct sched_domain_topology_level *tl)
-- 
2.20.1