[RFC PATCH v1 2/3] sched: threshold helper functions

[Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>]

Define group capacity threshold as a multiple of
impalance percentage at higher levels of sched_mc settings.

sched_mc=3 Group capacity increased by 25% (5 tasks on quad core)
sched_mc=4 Group capacity increased by 50% (6 tasks on quad core)
sched_mc=5 Group capacity increased by 100% (8 tasks on quad core)

*** RFC patch for discussion ***

Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
---

 kernel/sched.c |   21 +++++++++++++++++++++
 1 files changed, 21 insertions(+), 0 deletions(-)

diff --git a/kernel/sched.c b/kernel/sched.c
index b902e58..f88ed04 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3291,6 +3291,21 @@ static inline int get_sd_load_idx(struct sched_domain *sd,
 
 
 #if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
+
+static inline unsigned int group_capacity_bump_pct(struct sched_domain *sd)
+{
+	if (sched_mc_power_savings >= POWERSAVINGS_INCREASE_GROUP_CAPACITY_3)
+		return 100+(sd->imbalance_pct-100)*4;
+
+	if (sched_mc_power_savings >= POWERSAVINGS_INCREASE_GROUP_CAPACITY_2)
+		return 100+(sd->imbalance_pct-100)*2;
+
+	if (sched_mc_power_savings >= POWERSAVINGS_INCREASE_GROUP_CAPACITY_1)
+		return sd->imbalance_pct;
+
+	return 100;
+}
+
 /**
  * init_sd_power_savings_stats - Initialize power savings statistics for
  * the given sched_domain, during load balancing.
@@ -3433,6 +3448,12 @@ static inline int check_power_save_busiest_group(struct sd_lb_stats *sds,
 {
 	return 0;
 }
+
+static inline unsigned int group_capacity_bump_pct(struct sched_domain *sd)
+{
+	return 100;
+}
+
 #endif /* CONFIG_SCHED_MC || CONFIG_SCHED_SMT */