[PATCH 3/7] sched/fair: Correct unit of load_above_capacity

From: Dietmar Eggemann
Date: Fri Apr 29 2016 - 15:34:28 EST


From: Morten Rasmussen <morten.rasmussen@xxxxxxx>

In calculate_imbalance() load_above_capacity currently has the unit
[load] while it is used as being [load/capacity]. Not only is it wrong it
also makes it unlikely that load_above_capacity is ever used as the
subsequent code picks the smaller of load_above_capacity and the avg_load
difference between the local and the busiest sched_groups.

This patch ensures that load_above_capacity has the right unit
[load/capacity].

Signed-off-by: Morten Rasmussen <morten.rasmussen@xxxxxxx>
---
kernel/sched/fair.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index bc19fee94f39..c066574cff04 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -7016,9 +7016,11 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
local->group_type == group_overloaded) {
load_above_capacity = busiest->sum_nr_running *
SCHED_LOAD_SCALE;
- if (load_above_capacity > busiest->group_capacity)
+ if (load_above_capacity > busiest->group_capacity) {
load_above_capacity -= busiest->group_capacity;
- else
+ load_above_capacity *= SCHED_LOAD_SCALE;
+ load_above_capacity /= busiest->group_capacity;
+ } else
load_above_capacity = ~0UL;
}

--
1.9.1