blob: 70ac2451ab9eff15f316d062afcfa117800033ac (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
|
From f02fa9f5a150721451b41d9677f9c5f5710c09a9 Mon Sep 17 00:00:00 2001
From: Dietmar Eggemann <dietmar.eggemann@arm.com>
Date: Sun, 10 May 2015 15:17:32 +0100
Subject: [PATCH 62/92] sched: Consider a not over-utilized energy-aware system
as balanced
In case the system operates below the tipping point indicator,
introduced in ("sched: Add over-utilization/tipping point
indicator"), bail out in find_busiest_group after the dst and src
group statistics have been checked.
There is simply no need to move usage around because all involved
cpus still have spare cycles available.
For an energy-aware system below its tipping point, we rely on the
task placement of the wakeup path. This works well for short running
tasks.
The existence of long running tasks on one of the involved cpus lets
the system operate over its tipping point. To be able to move such
a task (whose load can't be used to average the load among the cpus)
from a src cpu with lower capacity than the dst_cpu, an additional
rule has to be implemented in need_active_balance.
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
(cherry picked from commit e604c981fa91a5e5522cd4a5a057880ab54d374c)
Signed-off-by: Gaku Inami <gaku.inami.xw@bp.renesas.com>
---
kernel/sched/fair.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 3c193f5..360e922 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -8103,6 +8103,10 @@ static struct sched_group *find_busiest_group(struct lb_env *env)
* this level.
*/
update_sd_lb_stats(env, &sds);
+
+ if (energy_aware() && !env->dst_rq->rd->overutilized)
+ goto out_balanced;
+
local = &sds.local_stat;
busiest = &sds.busiest_stat;
--
1.9.1
|
