Re: [PATCH 2/2] sched: add statistic for rq->max_idle_balance_cost

[Alex Shi <alex.shi@linaro.org>]

On 01/23/2014 02:10 AM, Jason Low wrote:
>>> > >  	P64(avg_idle);
>>> > > +	P64(max_idle_balance_cost);
>>> > >  #endif
>>> > >   	P(ttwu_count);
>> > 
>> > Not also the per-sd value in sd_alloc_ctl_domain_table() ?
> Yeah, tracking the sd->max_newidle_lb_cost can also be useful.
> 
> 

Thanks for suggestion!

I thought the sd->max_newidle_lb_cost keep changing. But yes, it's
still meaningful. 
BTW, in the pandaboard ES, sd balance cost is about 1~2ms.

---

>From d37e712b623fb6776d0caba8e4bd06460e26b84e Mon Sep 17 00:00:00 2001
From: Alex Shi <alex.shi@linaro.org>
Date: Tue, 21 Jan 2014 13:28:55 +0800
Subject: [PATCH] sched: add statistic for newidle load balance cost

Tracking rq->max_idle_balance_cost and sd->max_newidle_lb_cost
It's useful to track these values in debug mode.

Signed-off-by: Alex Shi <alex.shi@linaro.org>
---
 kernel/sched/core.c  | 7 +++++--
 kernel/sched/debug.c | 1 +
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index c3f3824..a046bc3 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -4293,7 +4293,7 @@ set_table_entry(struct ctl_table *entry,
 static struct ctl_table *
 sd_alloc_ctl_domain_table(struct sched_domain *sd)
 {
-	struct ctl_table *table = sd_alloc_ctl_entry(8);
+	struct ctl_table *table = sd_alloc_ctl_entry(9);
 
 	if (table == NULL)
 		return NULL;
@@ -4313,7 +4313,10 @@ sd_alloc_ctl_domain_table(struct sched_domain *sd)
 		sizeof(int), 0644, proc_dointvec_minmax);
 	set_table_entry(&table[6], "name", sd->name,
 		CORENAME_MAX_SIZE, 0444, proc_dostring);
-	/* &table[7] is terminator */
+	set_table_entry(&table[7], "max_newidle_lb_cost",
+		&sd->max_newidle_lb_cost,
+		sizeof(long), 0644, proc_doulongvec_minmax);
+	/* &table[8] is terminator */
 
 	return table;
 }
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 1e43e70..9ecd861 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -315,6 +315,7 @@ do {									\
 	P(sched_goidle);
 #ifdef CONFIG_SMP
 	P64(avg_idle);
+	P64(max_idle_balance_cost);
 #endif
 
 	P(ttwu_count);
-- 
1.8.1.2

-- 
Thanks
    Alex