[RFC PATCH 11/16 v3] Make wakeup bias threshold changeable via sysctl

[Yuyang Du <yuyang.du@intel.com>]

In wakeup balance, we bias wakee and waker (in this order) if it is capable
of handling the wakee task.

sysctl_sched_cc_wakeup_threshold is the threshold to see whether the CPU
is capable, and can be changed by sysctl tool

Signed-off-by: Yuyang Du <yuyang.du@intel.com>
---
 include/linux/sched/sysctl.h |    1 +
 kernel/sysctl.c              |    7 +++++++
 2 files changed, 8 insertions(+)

diff --git a/include/linux/sched/sysctl.h b/include/linux/sched/sysctl.h
index f8a3e0a..f1e90c7 100644
--- a/include/linux/sched/sysctl.h
+++ b/include/linux/sched/sysctl.h
@@ -38,6 +38,7 @@ extern unsigned int sysctl_sched_child_runs_first;
 
 #ifdef CONFIG_SMP
 extern unsigned int sysctl_sched_cc_sum_period;
+extern unsigned int sysctl_sched_cc_wakeup_threshold;
 #endif
 
 enum sched_tunable_scaling {
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 13aea95..77a5aa5 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -1098,6 +1098,13 @@ static struct ctl_table kern_table[] = {
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec,
 	},
+	{
+		.procname	= "sched_cc_wakeup_threshold",
+		.data		= &sysctl_sched_cc_wakeup_threshold,
+		.maxlen		= sizeof(sysctl_sched_cc_wakeup_threshold),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+	},
 #endif
 	{ }
 };
-- 
1.7.9.5