Merge branch 'cacule-5.13-rdb-autogroup-testing' into cacule-5.13

CacULE r3

Author: hamadmarri

include/linux/sched/sysctl.h

@@ -35,11 +35,11 @@ extern unsigned int sysctl_sched_wakeup_granularity;
 #ifdef CONFIG_CACULE_SCHED
 extern unsigned int interactivity_factor;
 extern unsigned int cacule_max_lifetime;
-extern int cacule_yield;
 extern unsigned int cache_factor;
 extern unsigned int cache_divisor;
 extern unsigned int starve_factor;
 extern unsigned int starve_divisor;
+extern int cacule_yield;
 #endif
 
 enum sched_tunable_scaling {

init/Kconfig

@@ -844,6 +844,40 @@ config CACULE_SCHED
 
 	  If unsure, say Y here.
 
+config CACULE_RDB
+	bool "RDB (Response Driven Balancer)"
+	default y
+	depends on CACULE_SCHED
+	help
+	  This is an experimental load balancer for CacULE. It is a lightweight
+	  load balancer which is a replacement of CFS load balancer. It migrates
+	  tasks based on their interactivity scores.
+
+	  If unsure, say Y here.
+
+config RDB_INTERVAL
+	int "RDB load balancer interval"
+	default 19
+	depends on CACULE_RDB
+	help
+	  This is an interval to control load balance time period.
+	  The trigger_load_balance runs in every tick. For High HZ values, the
+	  load balance could be overwhelming. RDB load balance includes rq locking
+	  which can reduce the performance. The balance interval can help to avoid
+	  running load balance on every tick. For example, RDB_INTERVAL=3 will
+	  only run load balance every 3ms. Setting RDB_INTERVAL depends on HZ.
+	  If you want load balancer run every 2ms while HZ=500 then it is not
+	  needed and better to set RDB_INTERVAL=0 since 500HZ already (1000ms
+	  / 500HZ = 2ms). However, if you have 1000HZ and want to avoid load
+	  balancer from running every 1ms, you could set RDB_INTERVAL=4ms for
+	  example to make load balancer run every 4ms. Less RDB_INTERVAL values
+	  (or 0 to disable) could make sure tasks are balanced ASAP, but with
+	  the cost of locking/blocking time. High RDB_INTERVAL values can relax
+	  balancing locking but with the cost of imbalanced workload for that
+	  period of time (i.e. if RDB_INTERVAL=100ms) there will be no balancing
+	  for 100ms (except for newidle_balance which is not effected by RDB_INTERVAL).
+
+	  If in doubt, use the default value.
 
 #
 # For architectures that want to enable the support for NUMA-affine scheduler

kernel/sched/core.c

@@ -8141,7 +8141,11 @@ void __init sched_init(void)
 #endif
 
 #ifdef CONFIG_CACULE_SCHED
-	printk(KERN_INFO "CacULE CPU scheduler v5.13-r2 by Hamad Al Marri.");
+#ifdef CONFIG_CACULE_RDB
+	printk(KERN_INFO "CacULE CPU scheduler (RDB) v5.13-r3 by Hamad Al Marri.");
+#else
+	printk(KERN_INFO "CacULE CPU scheduler v5.13-r3 by Hamad Al Marri.");
+#endif
 #endif
 
 	wait_bit_init();