[13/14] sched: update the cpu_power

Commit Message

Vincent Guittot April 25, 2013, 5:23 p.m. UTC

The cpu_power is updated for CPUs that don't participate to the packing
effort. We consider that their cpu_power is allocated to idleness as it could
be allocated by rt. So the cpu_power that remains available for cfs, is set to
min value (i.e. 1)

Signed-off-by: Vincent Guittot <[e-mail]>
---
 kernel/sched/fair.c |   35 ++++++++++++++++++++---------------
 1 file changed, 20 insertions(+), 15 deletions(-)

Comments

Morten Rasmussen May 22, 2013, 3:46 p.m. UTC | #1

On Thu, Apr 25, 2013 at 06:23:29PM +0100, Vincent Guittot wrote:
> @@ -4596,8 +4597,12 @@ static void update_cpu_power(struct sched_domain *sd, int cpu)
>  	cpu_rq(cpu)->cpu_available = power;
>  	sdg->sgp->power_available = power;
>  
> +	if (!is_my_buddy(cpu, cpu))
> +		power = 1;
> +

Using your fix for is_my_buddy() for patch 11 the above will always be
true when sched_packing_mode is to anything else than
SCHED_PACKING_FULL. So cpu_power for all cpus in
SCHED_PACKING_{DEFAULT,NONE} is 1.

As far is I understand, this is not the intention?

Cheers,
Morten

>  	cpu_rq(cpu)->cpu_power = power;
>  	sdg->sgp->power = power;
> +
>  }
>  
>  void update_group_power(struct sched_domain *sd, int cpu)
> -- 
> 1.7.9.5
> 
>

Vincent Guittot May 22, 2013, 3:58 p.m. UTC | #2

On 22 May 2013 17:46, Morten Rasmussen <[e-mail]> wrote:
> On Thu, Apr 25, 2013 at 06:23:29PM +0100, Vincent Guittot wrote:
>> @@ -4596,8 +4597,12 @@ static void update_cpu_power(struct sched_domain *sd, int cpu)
>>       cpu_rq(cpu)->cpu_available = power;
>>       sdg->sgp->power_available = power;
>>
>> +     if (!is_my_buddy(cpu, cpu))
>> +             power = 1;
>> +
>
> Using your fix for is_my_buddy() for patch 11 the above will always be
> true when sched_packing_mode is to anything else than
> SCHED_PACKING_FULL. So cpu_power for all cpus in
> SCHED_PACKING_{DEFAULT,NONE} is 1.
>
> As far is I understand, this is not the intention?

yes, the too quick fix for 11/14 has not fixed anything... the final
fix is available in git://git.linaro.org/people/vingu/kernel.git
sched-pack-small-tasks-v4-fixed.

And it will be part of the next version that i prepare

Vincent
>
> Cheers,
> Morten
>
>>       cpu_rq(cpu)->cpu_power = power;
>>       sdg->sgp->power = power;
>> +
>>  }
>>
>>  void update_group_power(struct sched_domain *sd, int cpu)
>> --
>> 1.7.9.5
>>
>>
>

Patch

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 756b1e3..54c1541 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -224,12 +224,12 @@  void update_packing_domain(int cpu)
 
 		/* loop the sched groups to find the best one */
 		for (tmp = sg->next; tmp != sg; tmp = tmp->next) {
-			if (tmp->sgp->power * pack->group_weight >
-					pack->sgp->power * tmp->group_weight)
+			if (tmp->sgp->power_available * pack->group_weight >
+				pack->sgp->power_available * tmp->group_weight)
 				continue;
 
-			if ((tmp->sgp->power * pack->group_weight ==
-					pack->sgp->power * tmp->group_weight)
+			if ((tmp->sgp->power_available * pack->group_weight ==
+				pack->sgp->power_available * tmp->group_weight)
 			 && (cpumask_first(sched_group_cpus(tmp)) >= id))
 				continue;
 
@@ -269,12 +269,12 @@  void update_packing_buddy(int cpu, int activity)
 
 	/* loop the sched groups to find the best one */
 	for (tmp = sg->next; tmp != sg; tmp = tmp->next) {
-		if ((tmp->sgp->power * pack->group_weight) >
+		if ((tmp->sgp->power_available * pack->group_weight) >
 			(pack->sgp->power_available * tmp->group_weight))
 			continue;
 
-		if (((tmp->sgp->power * pack->group_weight) ==
-			 (pack->sgp->power * tmp->group_weight))
+		if (((tmp->sgp->power_available * pack->group_weight) ==
+			 (pack->sgp->power_available * tmp->group_weight))
 		 && (cpumask_first(sched_group_cpus(tmp)) >= id))
 			continue;
 
@@ -285,20 +285,20 @@  void update_packing_buddy(int cpu, int activity)
 		id = cpumask_first(sched_group_cpus(pack));
 	}
 
-	if ((cpu == id) || (activity <= power_of(id))) {
+	if ((cpu == id) || (activity <= available_of(id))) {
 		per_cpu(sd_pack_buddy, cpu) = id;
 		return;
 	}
 
 	for (tmp = pack; activity > 0; tmp = tmp->next) {
-		if (tmp->sgp->power > activity) {
+		if (tmp->sgp->power_available > activity) {
 			id = cpumask_first(sched_group_cpus(tmp));
-			activity -= power_of(id);
+			activity -= available_of(id);
 			if (cpu == id)
 				activity = 0;
 			while ((activity > 0) && (id < nr_cpu_ids)) {
 				id = cpumask_next(id, sched_group_cpus(tmp));
-				activity -= power_of(id);
+				activity -= available_of(id);
 				if (cpu == id)
 					activity = 0;
 			}
@@ -306,7 +306,7 @@  void update_packing_buddy(int cpu, int activity)
 			id = cpu;
 			activity = 0;
 		} else {
-			activity -= tmp->sgp->power;
+			activity -= tmp->sgp->power_available;
 		}
 	}
 
@@ -3369,7 +3369,8 @@  find_idlest_group(struct sched_domain *sd, struct task_struct *p,
 		}
 
 		/* Adjust by relative CPU power of the group */
-		avg_load = (avg_load * SCHED_POWER_SCALE) / group->sgp->power;
+		avg_load = (avg_load * SCHED_POWER_SCALE)
+				/ group->sgp->power_available;
 
 		if (local_group) {
 			this_load = avg_load;
@@ -3551,10 +3552,10 @@  static int get_cpu_activity(int cpu)
 
 	if (sum == period) {
 		u32 overload = rq->nr_running > 1 ? 1 : 0;
-		return power_of(cpu) + overload;
+		return available_of(cpu) + overload;
 	}
 
-	return (sum * power_of(cpu)) / period;
+	return (sum * available_of(cpu)) / period;
 }
 
 /*
@@ -4596,8 +4597,12 @@  static void update_cpu_power(struct sched_domain *sd, int cpu)
 	cpu_rq(cpu)->cpu_available = power;
 	sdg->sgp->power_available = power;
 
+	if (!is_my_buddy(cpu, cpu))
+		power = 1;
+
 	cpu_rq(cpu)->cpu_power = power;
 	sdg->sgp->power = power;
+
 }
 
 void update_group_power(struct sched_domain *sd, int cpu)