Re: [PATCH v9 03/10] sched: remove frequency scaling from cpu_capacity
On Mon, Nov 03, 2014 at 04:54:40PM +, Vincent Guittot wrote: > Now that arch_scale_cpu_capacity has been introduced to scale the original > capacity, the arch_scale_freq_capacity is no longer used (it was > previously used by ARM arch). Remove arch_scale_freq_capacity from the > computation of cpu_capacity. The frequency invariance will be handled in the > load tracking and not in the CPU capacity. Just a note: Yes, we are scaling the load tracking of each task to compensate for frequency scaling. I think that is all fine. Later we will have to feed the current frequency into the energy model as well to figure out if putting more tasks on a cpu will/should cause the frequency to increase or not. We don't need it for now and don't need to add it in the commit message. It is just a reminder that we may actually want to use arch_scale_freq_capacity() combined with cpu_capacity to provide this input to the energy model later. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH v9 03/10] sched: remove frequency scaling from cpu_capacity
Now that arch_scale_cpu_capacity has been introduced to scale the original capacity, the arch_scale_freq_capacity is no longer used (it was previously used by ARM arch). Remove arch_scale_freq_capacity from the computation of cpu_capacity. The frequency invariance will be handled in the load tracking and not in the CPU capacity. arch_scale_freq_capacity will be revisited for scaling load with the current frequency of the CPUs in a later patch. Signed-off-by: Vincent Guittot --- kernel/sched/fair.c | 7 --- 1 file changed, 7 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index a171e1b..a96affd 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5823,13 +5823,6 @@ static void update_cpu_capacity(struct sched_domain *sd, int cpu) sdg->sgc->capacity_orig = capacity; - if (sched_feat(ARCH_CAPACITY)) - capacity *= arch_scale_freq_capacity(sd, cpu); - else - capacity *= default_scale_capacity(sd, cpu); - - capacity >>= SCHED_CAPACITY_SHIFT; - capacity *= scale_rt_capacity(cpu); capacity >>= SCHED_CAPACITY_SHIFT; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/